What Is a Seamless Stainless Steel TP904L Tube?
UNS N08904 Super Austenitic Stainless Steel for Sulfuric Acid & Severe Corrosion Resistance
1. What is a Seamless TP904L Stainless Steel Tube?
TP904L Seamless Stainless Steel Tube is supplied for high nickel-molybdenum-copper alloying for reducing-acid and chloride service. The size range shown (OD 6–257 mm; WT 0.5–35 mm) is the overall capability across this product family, not a per-grade commitment. Confirm the specific OD × WT × length combination for the ordered grade in the quotation. The governing specification must be stated on the purchase order: ASTM B677 / ASME SB677 or project-specific tube specification. Chemistry, mechanical properties, heat treatment, dimensional tolerance, NDT and certification must be reported against the ordered standard and material heat; do not treat typical values as guaranteed acceptance limits.
Manufactured from a solid billet using a seamless process (hot piercing + cold drawing/finishing), TP904L provides:
- No longitudinal weld seam, avoiding weld-related corrosion risks
- Uniform microstructure → consistent corrosion resistance
- Superior pressure resistance → ideal for critical piping systems
The grade is characterized by:
- High Chromium (Cr) and Nickel (Ni) content
- Addition of Molybdenum (Mo) and Copper (Cu)
- Very low carbon content (≤ 0.020%)
This unique composition ensures excellent resistance to reduction acids, especially sulfuric acid, while maintaining weldability and structural stability.
2. Key Features & Technical Advantages
Outstanding Sulfuric Acid Resistance
Specifically engineered for sulfuric acid service across a wide concentration range (under moderate temperatures). Also performs well in phosphoric acid and acetic acid environments.
Excellent Pitting & Crevice Corrosion Resistance
High Mo (4–5%) and Cu content significantly improve resistance to localized corrosion, with a high PREN (Pitting Resistance Equivalent Number).
Superior Resistance to Chloride SCC
Nickel content (23–28%) provides strong resistance to chloride-induced stress corrosion cracking (SCC), making it suitable for marine and industrial environments.
Excellent Weldability & Fabricability
Low carbon content prevents sensitization, ensuring corrosion resistance in the heat-affected zone (HAZ) without the need for post-weld heat treatment.
Non-Magnetic Austenitic Structure
Remains non-magnetic even after cold working, suitable for specialized industrial and electronic applications.
Product Specifications and Data
To provide a comprehensive overview of this high-performance material, here are the detailed technical specifications and performance data for Seamless Stainless Steel TP904L Tube.
Stainless Steel 904L is specifically designed to maintain its strength and shape in high-stress, corrosive environments.
Equivalent Grade
| UNS | Common grade name | EN material number | EN steel name | JIS grade | GB/T grade |
|---|---|---|---|---|---|
| N08904 | 904L | 1.4539 | X1NiCrMoCu25-20-5 | SUS890L | 015Cr21Ni26Mo5Cu2 |
Grade correspondence does not make ASTM, ASME, EN, JIS and GB delivery requirements interchangeable. Confirm chemistry, heat treatment, mechanical properties, dimensions, testing and certification against the purchase specification. Approximate or unconfirmed correspondences retain their qualification. See the grade designation index.
Chemical Composition
| C | Si | Mn | P | S | Cr | Ni | Mo | Cu |
|---|---|---|---|---|---|---|---|---|
| ≤0.020 | ≤1.00 | ≤2.00 | ≤0.045 | ≤0.030 | 19.00–23.00 | 23.00–28.00 | 4.00–5.00 | 1.00–2.00 |
Data source: ASTM B677 / ASME SB677 or project-specific tube specification ≤ heat-analysis acceptance limits per the governing standard. Confirm the values against the ordered edition and the MTC.
Typical Physical Properties
These physical properties highlight the material’s ability to perform reliably under a wide range of conditions.
| Tensile Strength | Yield Strength | Elongation | Hardness |
|---|---|---|---|
| ≥ 490 MPa | ≥ 215 MPa | ≥ 35% | ≤ 192 HBW / 200 HV / 90 HRB |
Note: Typical values for reference only — not acceptance limits. Physical and mechanical properties are reported on the MTC against the ordered standard, product form and condition.
| Density | Melting Point | Thermal Expansion | Thermal Conductivity | Modulus of Elasticity | Electrical Resistivity |
|---|---|---|---|---|---|
| 8.0 g/cm³ | 1300 – 1390 °C approx. | 16.5 μm/m·°C (20-100°C) | 13.9 W/m·K (20°C) | 195 GPa | 0.85 × 10⁻⁶ Ω·m (20°C) |
ASTM A1016/A1016M Tube Size Tolerance Chart
Size Tolerance Chart (mm)
| Specified Outside Diameter (OD) (Inches) | Permissible Variations in OD (± Inches) |
|---|---|
| 1⁄2 to 1 | ±0.005 |
| Over 1 to 1-1⁄2 | ±0.008 |
| Over 1-1⁄2 to 2 | ±0.010 |
| Over 2 to 2-1⁄2 | ±0.012 |
| Over 2-1⁄2 to 3-1⁄2 | ±0.014 |
| Over 3-1⁄2 to 5 | ±0.020 |
Tolerance basis: permitted variations per the governing specification stated on this page and the applicable general-requirements standard (ASTM A1016 / ASME SA1016) for the ordered product form; the wall-thickness and length variations in this section follow the same basis.
| Specified Outside Diameter (OD) (Inches) | Specified Wall Thickness (WT) (Inches) | Permissible Variation (± Inches) |
|---|---|---|
| 1⁄2 to 1 (Inclusive) | 0.025 to 0.065(Inclusive) | ±0.010 |
| Over 0.065to 0.134 (Inclusive) | ±0.012 | |
| Over 1 to 1-1⁄2 (Inclusive) | 0.025 to 0.065 (Inclusive) | ±0.010 |
| Over 0.065 to 0.134 (Inclusive) | ±0.012 | |
| Over 1-1⁄2 to 2 (Inclusive) | 0.025 to 0.049 (Inclusive) | ±0.011 |
| Over 0.049 to 0.083 (Inclusive) | ±0.012 | |
| Over 0.083 to 0.148 (Inclusive) | ±0.014 | |
| Over 2 to 2-1⁄2 (Inclusive) | 0.032 to 0.065 (Inclusive) | ±0.013 |
| Over 0.065 to 0.109 (Inclusive) | ±0.015 | |
| Over 0.109 to 0.165 (Inclusive) | ±0.017 | |
| Over 2-1⁄2 to 3-1⁄2 (Inclusive) | 0.032 to 0.165 (Inclusive) | ±0.020 |
| Over 0.165 to 0.220 (Inclusive) | ±0.025 | |
| Over 3-1⁄2 to 5 (Inclusive) | 0.083 to 0.165 (Inclusive) | ±0.025 |
| Over 0.165 to 0.220 (Inclusive) | ±0.030 |
Length Tolerance
For Specific Cut Lengths, the standard tolerance is +1⁄8 in. [3 mm], -0 in. [0 mm].
Important Note: The values presented here are based on the dimensional tolerance tables in ASTM A1016/A1016M (General Requirements for Ferritic Alloy Steel, Austenitic Alloy Steel, and Stainless Steel Tubes), contains other essential requirements like straightness and details for tubes with ODs outside of this range. Always consult the latest official standard for design and procurement.
Common Industrial Applications
TP904L seamless tubes are widely used in highly corrosive and acid-rich environments, including:
Chemical & Acid Processing
- Sulfuric acid production systems
- Phosphoric and acetic acid equipment
- Heat exchangers and reactors
Oil & Gas / Refinery
- Sour gas handling systems
- Gas scrubbing equipment
- Corrosion-resistant piping
Environmental Engineering
- Flue Gas Desulfurization (FGD) systems
- Scrubbers and exhaust treatment systems
Pulp & Paper Industry
- Bleaching systems
- Chemical washing units
Pharmaceutical & Food Industry
- High-purity, corrosion-free process systems
Advanced Manufacturing Process
- Raw Material Selection & Billet Heating
High-quality alloy billets ensure consistent composition and performance. - Hot Piercing & Seamless Forming
Produces hollow tubes with no longitudinal weld seam. - Cold Drawing / Cold Rolling
Achieves precise dimensions and superior surface finish. - Solution Annealing
Restores corrosion resistance and mechanical properties. - Full Non-Destructive Testing (NDT)
- Ultrasonic Testing (UT)
- Eddy Current Testing (ET)
- Hydrostatic Testing
100% Quality Assurance & Certification
We provide full quality control and certification to meet global project requirements:
- EN 10204 3.1 Material Test Certificates (MTC) as standard; 3.2 on arrangement
- 100% PMI (Positive Material Identification)
- NDT Testing: UT, ET, Hydrostatic Test
Frequently Asked Questions
What sizes are available for TP904L seamless tube?
The overall range is OD 6–257 mm; WT 0.5–35 mm. Requirements outside this range are reviewed against mill capability on request.
Which specification governs TP904L seamless tube?
ASTM B677 / ASME SB677 or project-specific tube specification is the governing specification for TP904L seamless tube. The edition in force at order time is stated on the quotation and purchase order; chemistry, mechanical properties, heat treatment, dimensions and testing are reported against the ordered standard and material heat.
What inspection documents are provided?
Each order is documented with a mill test certificate stating heat chemistry and mechanical test results. EN 10204 3.1 certification, hydrostatic testing, eddy-current or ultrasonic inspection and PMI are performed when specified in the purchase order.
Technical review: page data reviewed by the Xinzhe technical desk on 2026-09-27. Chemistry acceptance limits are compiled from the governing ASTM/ASME specification stated on this page; mechanical and physical values are typical reference data and are not acceptance guarantees. Values must be confirmed against the standard edition in force at order time and the material test certificate.
Ready to Request a Quotation?
Send the size (OD and wall or schedule), quantity, length, end finish and the inspection items you need as acceptance criteria — you will get a written quotation stating the specification and edition, delivery condition, documents included and lead time.
For the same grade in pipe form, see the TP904L seamless pipe. To compare other grades and size combinations, browse the Stainless Steel Seamless Pipe category. Minimum order quantity and lead time are confirmed on enquiry against the ordered grade, size and quantity.
